Stacking apparatus



Sept. 15, 1964 H. J. KISTNER 3,148,879

STACKING APPARATUS Filed Aug. 31, 1961 E/VTOR a $22 24 nvv t b HAROLD J. KISTNER '61 FIG. 3 24750;}

A 77' ORNE' Y United States Patent 3,148,379 STACKING APlARATUS Harold J. Kistner, Endicott, N.Y., assignor to International Business Machines Corporation, New York, N.Y., a corporation of New York Filed Aug. 31, E61, Ser. No. 135,34

8 Claims. (Cl. 271-87) This invention relates toapparatus for high-speed stacking of out forms having a certain degree of rigidity and, more particularly, relates to such apparatus which is compact, inexpensive and readily preadjustable to stack forms of any desired size Within a preselected range of sizes.

As attempts are made to increase the rate at which forms are stacked, numerous problems are encountered. For example, it becomes more difficult to' stop the forms quickly without damage. Also, in-flight collisions must be avoided in order to prevent damage or misstacking of the forms. Forms must be stacked reliably despite the varying physical characteristics resulting from changes in humidity, warpage, or slight variations in size due to manufacturing tolerances. Devices previously proposed to satisfy the various requirements for high-speed stacking are not adapted to be readily adjustable to provide reliable operation over a wide range of form sizes- They employ deflectors or guides which are curved for use with forms of certain sizes. Also, they are relatively eX pensive in that they comprise a plurality of parts, many of complexly curved shapes which are ditficult and ex-. pensive to manufacture.

The principal object of this invention is therefore to provide an improved, relatively inexpensive, high-speed stacking apparatus wherein the parts are so arranged as to be readily adjustable to stack forms of any pre-selected size over a wide range of permissible sizes.

According to the invention, means including the previously stacked forms bow each form longitudinally before its leading edge strikes a stop means. This stop means is preferably yieldable, better to dissipate the kinetic energy of the form to prevent damage thereto and then cffectively rebound the form toward ararnp. At orshortly after the instant a form strikes the stop means, its trailing edge will pass a point where the ramp, diverges from the approach path of the form. Thereupon, as forward progress of the form is being halted by the .stop means, the' trailing edge of the form will swing laterally across the ramp and out of the path of the succeeding form. After the form has started to swing laterally crosswise of the v ramp, the energy stored in the yieldable stop means (if used) will become effective to drive the form downward .toward the. ramp. The form will come to restwith its trailing edge on a stack-supporting platform at the base of the ramp and will be stacked flatwise in substantially an upright position against the'formspreviously stacked;

Before striking the stop means, each form is preferably accelerated somewhat above the main transport speed by to control an electrical circuit. 7 This. circuit'is closed;

when and as long as the trailing edge of any formis'be tween the spaced sensing elements. Closureof the circuit pulses an electro-magnet topull the continuouslyrunning accelerator roll into frictional contact with the form.

.The foregoing and other objects, features and advan- 1 tages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the acco'mpanying 'drawa ing, wherein:

roll 16 is continuously rotated 'at a peripheral speed slighti "ice ing apparatus with the card levers removed for sake of clarity; and

FIG. 3 is a diagram of the circuitry for controlling operation of a stacker magnet.

Description Referring to FIGS. 1 and 2, the stacking apparatus embodying the invention comprises transversely spaced rolls 1 which cooperate with respective driven rolls 2 to advance forms, such as record cards 3, successively along a predetermined path. After leaving the rolls 1, 2, each card is diverted upward at generally a 45 angle from a substantially horizontal direction by two closely spaced guides 4, 5. Formed integrally with the upper or exit end of lower guide 4 is a ramp 6 that is inclined angularly downward at short distance toward a platform 7. I

The platform 7 has a card-supporting, generally horizontal surface 8 on which cards are stackable upright on their trailing edges.' An element 9 is supported onthe platform for movement in directions toward and away from the ramp. This element is biased toward the ramp 6 by a suitably anchored spring 1t! and acts against the fiat sides of the cards stacked on the platform to maintain the cards in compacted side-by-side relation. However, as the thickness of the stack increases, the support element 9v yields as required against the resistance of spring 10.

After the leading edge 'of a card advances beyond. the exit end of guides 4, 5, and past the upper edge of the ramp 6, thecard contacts and slides along the Hat side of the card last stacked (or the support element 9, in'the case of the firstcard to be stacked). 'The card advances upward toward contact with a-stop. This stop is preferably in the form of a bifurcated cantilever-supported yieldable stop spring 11. Upon contacting and displacing this spring 11, the kinetic energy of the upwardly moving card is dissipated and energy is stored in said spring. After the trailing edge of the card passes out of the guides 4, 5 and slightly above the upper end of ramp 6 and the spring has'brought the card'to'a stop, the card willbe rebounded generally toward the ramp by the energy stored in spring 11.

, Meanwhile, in order to assure that the card is quickly snapped out of the path of asucCeeding card after striking' the spring 11, means are provided for bowing the card longitudinally as its leading edge approaches said" spring. .This means comprises the cards already stacked (or thesupport element 9) and the curved lower end 12 of a fixed U-shapedchannelor bracket13. This channel has a notched surface of rack 14 forireceiving suitable latching means." For sake of"simplifiedfillustration, this latching means is shown as a spring-biased detent 15" that "is secured'to the stop spring '11. ..'The spring 11 projects through an elongated vertical slot'in the channel 13; :and' a detent "15 is manually disengageable from the rack 14 to permit spring 11 to be moved vertically tofany'one' of anumber ofpositions andthen latched in a selected position by projection, of detent 15 into an appropriate notch in thetoothed rack'14. 'The position of spring-11 rr iay thus be readily preadjusted to accommodate, cards of wide-v ly varying lengths, forfexample, varying 'anywher'efrom '22 columns to columns.

A roll-16 is provided to prevent deceleration. of a'card as it moves upwardly toward stop spring llafter leaving 'the last set of transport rolls 1,2. This roll'16..-i'sdisposed such thatjitstangent point is adjacent and at right angles to the upper end of ramp 6; As illustrated, this ,ment 9 .if.'no cards have'already been stacked). curved end 12 land previously stacked cards (or element strikesstop spring 11.

r) 1y greater than that of rolls 1 to accelerate the cards toward the stop spring 11; and the roll 16 is normally spaced slightly away from a card but is rocked into frictional driving contact with a card upon energization of an electro-magnet 17. More specifically, roll 16 is mounted on a driven shaft 18 which is journaled in spaced arms 19 that, in turn, are rockably supported on a pin 20 carried by channel 13. When magnet 17 is energized, its armature 21-is attracted to cause it, through contact with the outer ends of arms 19, to rock the roll 16 a very slight distance clockwise (as viewed in FIG. 1) and frictionally drive a card 3 upward past ramp 6.

As shown in FIG. 3, energization of magnet 17 is controlled by circuitry including card. levers 22, 23 and a source of electrical energy, such as a, battery 24. When a card. touches the toe of card lever 22, it will rock the lever clockwise about a fulcrum pin 25 to open a normally closed contact a, When a card touches the toe of card lever 23, it will rock the card lever clockwise about a fulcrum pin 26 to close a normally open contact b. Hence, since card levers 22, 23 are disposed along the card feed path at points substantially between the rolls 1, 2 and between the roll 16 and ramp 6, respectively,

the circuit shown in FIG. 3 will be closed and energize magnet 17 only when so long as the trailing edge of a card 3 is between rolls 1 and 16.

The rolls 1, 2 and 16 may be driven by any suitable means. As illustrated, rolls 1 are carried on and driven by a suitably driven shaft 28 which, through gears 29, 30, drives a shaft 31 on which rolls 2 are mounted. Roll 16 is driven from shaft 31 via gears 32, 33, 34 and shaft 18. The ratios of the diameters of the gears 32, 33, 34 and the diameter of roll 16 are such in relation to the diameters of rolls 1, 2 that the peripheral speed of roll 16 will preferably be greater than that of rolls 1 and 2.

Two transversely spaced pushers 35 preferably are provided. They assure that cards which have snapped laterally away from the approach path of the succeeding card toward the stop 11 will be positively moved down ramp 6 and compacted in side-by-side relation against the cards of the stack. These pushers 35 are connected to a common rock shaft 36 so as to be repeatedly rocked forward through cut-outs or recesses 37 in the ramp 6 and "spring40 biases follower 39 into contact with an eccentric .cam 41 driven by'drive shaft 28, so that the pushers 35 will be periodically oscillated forward and rearward as above explained.

Summary of Operation 14- (assisted by calibrations on the channel 13, not shown) as necessary tospace thestop spring 11, when in its normal unflexed state, a distance above the ramp 6 substantially equal to the lengthof the particular card to be stacked. a

4 Assume acard'is being fed through rolls 1, 2.. Roli 16 will friction'ally drive 'the card ,only after the trailing .edge of the card from lateral restraint and permit the trailedge passes card lever 23 and ramp 6. Meanwhilefas the leading edge of the card passes be yond ramp '6, it will be guided by curved end 12 toward contact with the previously stacked cards- (or ele- The 9) will cooperate to bow the card longitudinally (i.e.,

from front torear) before the leading edge of the card After the card strikes the stop spring 11, its trailing The detent 15-is manually prepositioned along the rack edge will pass above ramp 6. This will free the trailing edge of the card from lateral restraint and permit the trailing portion of the card to snap leftward (as viewed in FIG. 1) laterally relative to the ramp. Meanwhile, the kinetic energy stored in the card will be dissipated and converted by the spring 11 to potential energy to bring upward movement of the card to a halt. Thereupon, and after the trailing edge of the card has snapped at least partially out of the approach path of the succeeding form, the potential energy stored in the spring 11 will become effective to rebound the card toward the ramp. The oscillating pushers 35will thereafter push the cards periodically down the ramp. This will positively prevent the cards from collecting on the ramp and will also assure they will be stacked in compacted side-by-siderelation against the pre-existing stack.

It is to be noted that to provide maximum stacking rates, the stop 11 should be a yieldable spring to assure that cards will be brought to a stop without damage and will be promptly snapped out of the path of a succeeding card. For low stacking rates, the yieldable stop spring 11 may be replaced by a stationary stop member, if desired; however use of the yieldable stop spring is preferred because it may be used with all stacking rates.

With anapparatus embodying the invention, cards ranging from 22 columns to 80 columns in length have been reliably stacked; and 80 column cards have been stacked at a rate exceeding 600 cards perminu te.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. In apparatus for stacking forms, means providing a surface against which the forms are stacked side-by-side with their trailing edges aligned, yieldable stop means engageable by the leading edge of each successive form, means for advancing the forms successively toward 'the stop means, guide means for guiding each form towithin about one form length of the stop means, and means including previously stacked forms for bowing each form from front to rear after it leaves the guide means and before its leading edge strikes said stop means sothat after such striking the trailing edge will diverge from said guide means and snap out of the path of the succeeding form and toward said surface and previously stacked forms.

2. In apparatus preadjustable' for stacking forms of selectably different lengths, means providing a support surface on whichthe forms are stacked side-by-side with forms after each form strikes said stop means, means for previously stacked forms.

adjusting the position of said stop means at a distance from said guide substantially equal to the length of the forms ,tobe stacked, meansfor advancingthe forinssuccessively toward the stop means, and means including previously stacked forms for bowing each form from-front to rear after it passes the guide so that after its edge strikes 'thestop means its trailing edge will move slightly beyond said guide and then'be freed to snap out of the path'of the succeeding form and toward saidsurface and the 3. In apparatus for stacking forms, means providing a surface against which the forms are stackable sidebytoward said stop means, a ramp extending angularly to- Ward the end of said surface remote from said element and diverging from said approach path at a point substantially one form length from said stop means, and means including previously stacked forms for bowing each form longitudinally before its leading edge strikes said stop means so that, as soon as its trailing edge passes said ramp, the form will tend to straighten and said trailing edge will move relative to said ramp and toward said surface and out of the approach path of the succeeding form, and energy stored in said stop means will concurrently be effective to rebound the form back toward said ramp.

4. The combination according to claim 3, including means operated intermittently between positions in which it is retracted behind the ramp and projects through the ramp for pushing repeatedly on the trailing portions of the forms to work the forms down the ramp into com pacted relation against the stack.

5. The combination according to claim 3, including means for adjusting the height of said stop means relative to the ramp to correspond substantially to the length of the particular forms being processed, whereby the apparatus is readily adjustable to stack forms of different lengths.

6. The combination according to claim 3, including two sensing means spaced along the approach path of the forms, accelerating means for accelerating the form, and means operative only while the trailing edge of a form is between the spaced sensing means to render said accelerating means effective to drive the form at an increased speed for its final approach toward contact with said stop means.

7. In an apparatus for stacking forms, a platform on which forms are stackable upright on their trailing edges, a ramp inclined downwardly toward the platform from a point slightly higher than the platform, yieldable stop means in the form of a leaf spring-like means cantilever supported and engageable by the leading edges of each form to dissipate its kinetic energy and spaced slightly more than a form length above the platform, means for advancing the forms successively toward the stop means, means including the pre-existing stack of forms for bowing each form longitudinally before its leading edge strikes said stop means so that, as soon as said trailing edge passes the point Where said ramp diverges from the approach path of the form, the trailing edge of the form will concurrently swing laterally out of the path of the succeeding form and downward toward said ramp.

8. In an apparatus for stacking forms, means providing a surface against which the forms are stacked sideby-side with their trailing edges aligned, yieldable stop means engageable by the leading edges of the forms, feed means for moving the forms at one velocity toward the stop means, accelerating means disposed between the feed means and stop means and substantially a form length before the stop means for accelerating the form for its final approach into contact with the stop means, control means for activating said accelerating means only while the trailing edge of each successive form is between said feed means and accelerating means, and means including previously stacked forms for bowing each form as it passes beyond the accelerating means and before its leading edge strikes said stop means so that after such striking, the trailing edge of such form will snap out of the path of the succeeding form and toward such surface and previously stacked forms.

References Cited in the file of this patent UNITED STATES PATENTS 2,626,800 Martin Jan. 27, 1953 2,771,293 Guttridge Nov. 20, 1956 2,822,171 Luning Feb. 4, 1958 2,933,313 Stobb Apr. 19, 1960 2,970,836 Smith Feb. 7, 1961 3,079,151 Maidment Feb. 26, 1963 

1. IN APPARATUS FOR STACKING FORMS, MEANS PROVIDING A SURFACE AGAINST WHICH THE FORMS ARE STACKED SIDE-BY-SIDE WITH THEIR TRAILING EDGES ALIGNED, YIELDABLE STOP MEANS ENGAGEABLE BY THE LEADING EDGE OF EACH SUCCESSIVE FORM, MEANS FOR ADVANCING THE FORMS SUCCESSIVELY TOWARD THE STOP MEANS, GUIDE MEANS FOR GUIDING EACH FORM TO WITHIN ABOUT ONE FORM LENGTH OF THE STOP MEANS, AND MEANS INCLUDING PREVIOUSLY STACKED FORMS FOR BOWING EACH FORM FROM FRONT TO REAR AFTER IT LEAVES THE GUIDE MEANS AND BEFORE ITS LEADING EDGE STRIKES SAID STOP MEANS SO THAT AFTER SUCH STRIKING THE TRAILING EDGE WILL DIVERGE FROM SAID 